A researcher conducts a hypothesis test to evaluate the effect of a treatment that is expected to increase scores. The hypothesis test produces a z score of z=2.27. If the researcher is using a one tailed test, what is the correct statistical decision?
A- fail to reject the null with a=0.5 or a=0.1
B- cannot answer with no further information
C- reject the null with 0.5 but not 0.1
D- reject the null with either 0.5 or 0.1